14 May 2007

The difference of a decade

Climate change may have passed a key tipping point that could mean temperatures rising more quickly than predicted and it being harder to tackle global warming, research suggests.

Scientists at Bristol University say a previously unexplained surge of carbon dioxide levels in the atmosphere in recent years is due to more greenhouse gas escaping from trees, plants and soils. Global warming was making vegetation less able to absorb the carbon pollution pumped out by human activity.

Such a shift would worsen the gloomy predictions of the UN's Intergovernmental Panel on Climate Change, which warned last week that there is less than a decade to tackle rising emissions to avoid the worst effects of global warming.

The prediction came as an equally stark warning was issued that global warming was contributing to increased conflict over dwindling resources.

At the moment about half of human carbon emissions are re-absorbed into the environment, but the fear among scientists is that increased temperatures will reduce this effect. Wolfgang Knorr, a climate researcher at Bristol, said: "We could be seeing the carbon cycle feedback kicking in, which is good news for scientists because it shows our models are correct. But it's bad news for everybody else." Measurements of carbon dioxide in samples of air show a sharp increase since the turn of the century, with unusually high levels in four of the past five years. The spike does not seem to match the pattern of increased emissions from fossil-fuel burning, and can only be partly explained by natural events such as fires and weather phenomena including El Nino.

Dr Knorr's team compared the high carbon dioxide measurements in the atmosphere for 2002-03 with simulations of how soils and plants, including trees, behave under different conditions. They found the extra carbon dioxide in the atmosphere could be accounted for by plants taking up less carbon because of unusually dry and hot conditions.

Writing in Geophysical Research Letters, they say: "We find that the remarkable feature of the 2002-03 anomaly seems to be that climate fluctuations - not only related to El Nino and occurring across all latitudes - acted together to create an unusually strong out-gassing of CO2 of the terrestrial biosphere. Further research will be required to investigate if this fluctuation carries features of projected future climate change."

The British Foreign Secretary, Margaret Beckett, warned on Thursday that climate change could spawn a new era of conflicts over water and other scarce resources. She said climate-driven conflicts were already under way in Africa. Underlying the Darfur crisis was a struggle between nomadic and pastoral communities for resources made more scarce through a changing climate.

Speaking at the Royal United Services Institute in London on Thursday, Mrs Beckett quoted evidence that a similar conflict was brewing in Ghana where Fulani cattle herdsmen are reportedly arming themselves to take on local farmers in a confrontation over water and land as climate change expands the Sahara Desert.

The Foreign Secretary said the Middle East - with 5 per cent of the world's population but only 1 per cent of its water - would be particularly badly affected, with Saudi Arabia, Iran and Iraq hard-hit by a drop in rainfall.

"Resource-based conflicts are not new, but in climate change we have a new and potentially disastrous dynamic."

Her speech echoed a similar warning from the European Commission in January that global warming could trigger regional conflicts, poverty, famine, mass migration and the spread of infectious diseases such as malaria and dengue fever.

The British Government has this year tried to focus global attention on climate change as a security threat, and Mrs Beckett used the British chairmanship of the United Nations security council in April to convene the council's first debate on the issue.

Meanwhile at the UN, a vote is due overnight on whether Zimbabwe will take over the chairmanship of the Commission on Sustainable Development, which oversees environmental issues in the developing world.

Guardian News & Media

'Disastrous dynamic', eh? Is that the understatement of the year or what? With all that I've read, I think I'm leaning more towards the the James Lovelock school of prognostication. Yes, very, very depressing and sobering predictions, but I don't think we've seen the tip of the iceberg (wow - is that a pun for something that will no longer exist in 50 years!) on the full effects of our out-of-control breeding and profligate consumption. If we think things are disturbing now, once the positive feedback loops kick in, we ain't seen nothing yet. What may come will astound us in hindsight. Or not? I hope I'm undeniably wrong on all counts.

I recall an argument I had with a Communist once about the sustainability of human population on the planet. He was convinced that we could completely alter the entire surface of the planet to house our expanding technological population of many billions more. I couldn't believe the myopic view of his claims. A 100% technological solution for everything. Housing is one thing, but what about feeding, pollution and garbage management? Biodiversity loss? Carbon sink loss? Where's this magical atomic sequencer that will create food from minerals and create useful products from those already consumed? Where does all this stuff come from or go to? What will be the source of the tremendous amount of energy required for such a process? Oh right, it hasn't been invented yet. But it definitely will, in time. The optimists have no doubt about that.

How much time do we need? We will have essentially released millions of years of sequestered climate gases into the atmosphere during the 200 short years of the Industrial Age, something akin to continent-size fires burning for centuries (without near as many particulates, which theoretically provide a cooling affect), and we still won't admit that there will be detrimental consequences to this action? Boy, we sure can delude ourselves fully and completely. That might be the most fascinating human trait of all to analyze when the time for reckoning our behaviours stares us straight in the face.

But what's the point worrying about it, right? It's very regrettable we can't go back and change things. I'm not sure why I'm so consumed by these ideas and why I feel so compelled to keep telling everyone about them. Some friends have told me to follow the tried-and-true "how I stopped worrying and learned to love the bomb" ideology, which actually makes some sense, especially for someone like me that has concluded that anything we do will be too little, too late to curtail the effects of our follies. Another bizarre human behaviour I can't really explain. Maybe in ten years?